Why in some instances does changing streamers makes a bigger difference?

Different streaming software/programs can make a huge difference for sure!

Regarding the hardware used, I believe a well-engineered device, of which there are many at various price points, running good quality streaming software properly, should outperform a device that is not for some reason, and that some more niche products may offer a unique house sound that appeals to some enough to justify the cost, but that’s about as far as I would go.  

With good streaming software, like Roon or Qobuz,, any common household computer, tablet or smart phone can be a formidable competitor by simply using an asynchronous USB connection to a good quality external DAC.

@knownothing Thanks - food for thought.

As I may have mentioned my present setup is the Monster unit that does have isolation between outputs designed to prevent noise generated by a component from affecting others, in addition to overall filtering.

Also my phono stage, T8, preamp & power amp are on MIT Z-cords which also have filtering.  Per the manufacturers instructions the K-01xdse uses the supplied cable, and the SRS-FS725 frequency standard (clock) is on a hospital grade cable, fed from a UPS as it is "always on".

I am not sure what improvement I could get from the significant cost to upgrade the PDU - but I'm keeping my eyes open for a good used bargain to test.

@mapman Yes.  You make the point that if you use asynch USB and a good quality DAC you do not need to spend huge dollars on source components. 

BUT you need to take care about any software if you are using a general purpose computing device (Mac, PC, Phone) as they can "process" the stream.  I think that I have read that Roon can do DSP & volume management which will affect the sound.

BUT you need to take care about any software if you are using a general purpose computing device (Mac, PC, Phone) as they can "process" the stream.  I think that I have read that Roon can do DSP & volume management which will affect the sound.

Yes except not just on "general purpose" devices.  All streamers use software and with DSP anything is possible, FBOFW.

I use Roon DSP extensively with both general purpose and dedicated streaming hardware devices.  I apply DSP in Roon primarily per room, regardless of what device is doing the streaming.   DAC, amps, speakers used also factor in, but not so much streaming source device.  YMMV, it can also depend on specifics of DAC used and connection type between streamer and DAC, but use of asynch USB from most any good quality, mainstream, modern streaming device (Apple, Windows (with dedicated WASAPI configured for use), Android, others) to a good quality modern DAC pretty much resolves that, as verified by recent listening comparison tests I have done with various streaming devices as the source into several good quality DACS. .

@retiredaudioguy 

Looks like you have taken steps manage power and stray noise.  If you are curious about trying a different device between the wall and your gear, the Vinshine Audio x Kinki Studio Taihang Power Enhancer mentioned by @tyray above has been very positively reviewed by several established audio reviewers, who like tyray also ended up replacing more expensive devices with the Tai Hang.  It only has 4 outlets, and I haven’t tried it myself, but it doesn’t cost an arm and a leg, and seems to get very high marks from users.

kn